No. Emails are considered correspondence, not IP: https://www.quora.com/Is-an-email-message-considered-intelle...

As for clean room implementations, that is true, except in California.

Here, it does not really hold in court at all:

You can leave one company to join another doing more or less the same thing (because non-competition clauses are banned here), as long as you do not copy the code itself.

It sounds like you and your uncle post are both programmers trying to look at things too much from a logically moral perspective, rather than actually how the courts view these things, since you aren't very familiar with the latter.